My tachometer and speedometer both only work about 25% of the time. I’ve checked all my fuses, everything is fine, everything else in the instrument cluster works 100% of the time. I’ve tried researching this problem online, and have been unable to find anyone with a similar problem. Can anyone help me?

I have exactly the same problem on my 1994 A4. Normally when starting up and both the tacho and speedo work they will work for the duration of the trip or until the car is switched off again. You have been adivised to get another cluster suggesting a broken wire. Surely a broken wire will not behave like this. I have taken my car to Audi 3 times and every time told me they could not fix it. Frustrating if I want to sell the vehicle as it will not pass roadworthy in this condition. Have you had any luck since? I am about to blast Audi head office in my country about it.